Effect of Copper Cobalt Oxide Composition on Oxygen Evolution Electrocatalysts for Anion Exchange Membrane Water Electrolysis

Chae-Yeon Kwon; Jae-Yeop Jeong; Juchan Yang; Yoo Sei Park; Jaehoon Jeong; Honghyun Park; Yangdo Kim; Sung Mook Choi

doi:10.3389/fchem.2020.600908

Effect of Copper Cobalt Oxide Composition on Oxygen Evolution Electrocatalysts for Anion Exchange Membrane Water Electrolysis

Front Chem. 2020 Nov 4:8:600908. doi: 10.3389/fchem.2020.600908. eCollection 2020.

Authors

Chae-Yeon Kwon^{1

2}, Jae-Yeop Jeong^{1

3}, Juchan Yang¹, Yoo Sei Park^{1

3}, Jaehoon Jeong¹, Honghyun Park⁴, Yangdo Kim³, Sung Mook Choi¹

Affiliations

¹ Materials Center for Energy Convergence, Surface Technology Division, Korea Institute of Materials Science (KIMS), Changwon, South Korea.
² School of Materials Science and Engineering, Gyeongsang National University, Jinju, South Korea.
³ Department of Materials Science and Engineering, Pusan National University, Busan, South Korea.
⁴ Department of Advanced Biomaterials Research, Materials Processing Innovation Research Division, Korea Institute of Materials Science (KIMS), Changwon, South Korea.

Abstract

Copper cobalt oxide nanoparticles (CCO NPs) were synthesized as an oxygen evolution electrocatalyst via a simple co-precipitation method, with the composition being controlled by altering the precursor ratio to 1:1, 1:2, and 1:3 (Cu:Co) to investigate the effects of composition changes. The effect of the ratio of Cu²⁺/Co³⁺ and the degree of oxidation during the co-precipitation and annealing steps on the crystal structure, morphology, and electrocatalytic properties of the produced CCO NPs were studied. The CCO_1:2 electrode exhibited an outstanding performance and high stability owing to the suitable electrochemical kinetics, which was provided by the presence of sufficient Co³⁺ as active sites for oxygen evolution and the uniform sizes of the NPs in the half cell. Furthermore, single cell tests were performed to confirm the possibility of using the synthesized electrocatalyst in a practical water splitting system. The CCO_1:2 electrocatalyst was used as an anode to develop an anion exchange membrane water electrolyzer (AEMWE) cell. The full cell showed stable hydrogen production for 100 h with an energetic efficiency of >71%. In addition, it was possible to mass produce the uniform, highly active electrocatalyst for such applications through the co-precipitation method.

Keywords: anion exchange membrane (AEM); coprecipitaion method; electrolysis; hydrogen production; oxygen evolution reaction (OER).